An automobile instrument panel has a structure in which a polyurethane foam layer is provided between a skin made of vinyl chloride resin and a substrate. The skin made of vinyl chloride resin changes in color and deteriorates in thermal aging resistance over time. One of factors causing such a change in color and the like of the skin is a chemical reaction that occurs in association with a transfer of tertiary amine to the skin made of vinyl chloride resin, which tertiary amine has been used as a catalyst during formation of the polyurethane foam layer. In order to prevent the change in color of the skin, studies were made as to an urethane-integrated foaming molded article in which a particulate catching agent for capturing a volatile organic compound generated in the polyurethane foam layer is (i) covered with a sheet having continuous air bubbles and (ii) provided in the vicinity of a part of an end of the polyurethane foam layer at which part the end of the polyurethane foam layer is sealed with the skin material and the substrate (see, for example, Patent Literature 1). However, the urethane-integrated foaming molded article has a part where the skin is in contact with the polyurethane foam layer. This makes it impossible to prevent, for a long period of time, the change in color of the skin material which change is caused by the chemical reaction, thereby deteriorating the thermal aging resistance of the skin material.
Further, studies were made as to a laminate in which (i) a foaming layer made of synthetic resin is provided so as to join a core material and a skin and (ii) holes, from which gas generated in the foaming layer is to be discharged, are formed in the core material (see, for example, Patent Literature 2). However, the laminate has a part where the skin is in contact with the foaming layer. This makes it impossible to prevent, for a long period of time, a change in color of the skin material which change is caused by the chemical reaction, thereby deteriorating thermal aging resistance of the skin material.
Furthermore, studies were made as to a molded article made up of (i) a polyurethane molded article, (ii) a skin layer which contains vinyl chloride resin and covers at least a part of a surface of the polyurethane molded article, and (iii) a layer of an amine catching agent sandwiched between the polyurethane molded article and the skin layer (see, for example, Patent Literature 3). However, the amine catching agent easily volatilizes, and it is impossible to prevent, for a long period of time, a transfer of tertiary amine to the skin layer made of the vinyl chloride resin. This makes it impossible to prevent, for a long period of time, a change in color of the skin layer which change is caused by the chemical reaction, thereby deteriorating thermal aging resistance of the skin layer.
Moreover, a vinyl chloride resin composition for powder molding, in which a specific trimellitate plasticizer is mixed, was studied as a raw material for a skin material of an automobile interior material (see, for example, Patent Literature 4). In order to improve thermal aging resistance of the skin material obtained by powder molding of the vinyl chloride resin composition for powder molding, it is necessary to increase an amount of the trimellitate plasticizer mixed. Such increase in the amount of the trimellitate plasticizer mixed causes stickiness due to the trimellitate plasticizer. Furthermore, studies were made as to a vinyl chloride resin composition for powder molding which contains (i) 100 parts by mass of vinyl chloride resin particles made of vinyl chlorine resin having an average polymerization degree of not less than 1500 and (ii) 110 parts by mass to 150 parts by mass of a specific trimellitate plasticizer (for example, see Patent Literature 5).